Voltage output circuit for electronic cigarette and electronic cigarette using circuit

ABSTRACT

A voltage output circuit and an electronic cigarette are provided. The voltage output circuit includes a control chip and a step-down switch chip. When a first switch element turns on, the modulation signal output terminal of the control chip outputs a pulse modulation signal to a first control terminal of the step-down switch chip, and access between a first access terminal and a second access terminal of the step-down switch chip is established, based on the effective pulse modulation signal. The output voltage of the second access terminal is less than a system power voltage. The voltage output circuit and the electronic cigarette outputs the pulse modulation signal to the step-down switch chip by the control chip, and the step-down switch chip outputs a suitable driving voltage to the load, such as a thermal wire, the voltage output circuit with simplified structure is adjustable and improved.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims all benefits accruing under 35 U.S.C. § 119 fromChina Patent Application No. 201820241963.4, filed on Feb. 9, 2018 inthe China National Intellectual Property Administration, the content ofwhich is hereby incorporated by reference. This application is acontinuation-in-part under 35 U.S.C. § 120 of international patentapplication PCT/CN2018/096121 filed Jul. 18, 2018.

FIELD OF THE INVENTION

The subject matter herein generally relates to voltage control,particularly relates to a voltage output circuit for an electroniccigarette and the electronic cigarette itself.

BACKGROUND

In order to improve users experience, electronic cigarettes provideseveral additional functions besides a smoking function, such as amultimedia browsing function, a touch operation function, a navigationfunction, and a solar charging function, these additional functions areused for promoting a sale of the electronic cigarettes.

For achieving the additional functions of the electronic cigarette, itis necessary to provide different voltages to different circuitscorresponding to the additional functions, especially the atomizingfunction which is the basic function of the electronic cigarettes andneeds to be guaranteed.

The structure of the voltage output circuit in the current electroniccigarettes is complex and does not provide accurate and suitable drivingvoltages to different circuits corresponding to different additionalfunctions. Thus, there is room for improvement in the art.

BRIEF DESCRIPTION OF THE FIGURES

Implementations of the present disclosure will now be described, by wayof example only, with reference to the attached figures.

FIG. 1 is a circuit diagram illustrating a first embodiment of a voltageoutput circuit.

FIG. 2 is a circuit diagram illustrating a second embodiment of avoltage output circuit.

FIG. 3 is a circuit diagram illustrating a third embodiment of a voltageoutput circuit.

FIG. 4 is a circuit diagram illustrating a first embodiment of anelectronic cigarette with the voltage output circuit.

FIG. 5 is a circuit diagram illustrating a fourth embodiment of avoltage output circuit.

FIG. 6 is a circuit diagram illustrating a second embodiment of anelectronic cigarette with the voltage output circuit.

DETAILED DESCRIPTION

It will be appreciated that for simplicity and clarity of illustration,where appropriate, reference numerals have been repeated among thedifferent figures to indicate corresponding or analogous elements. Inaddition, numerous specific details are set forth in order to provide athorough understanding of the embodiments described herein. However, itwill be understood by those of ordinary skill in the art that theembodiments described herein can be practiced without these specificdetails. In other instances, methods, procedures, and components havenot been described in detail so as not to obscure the related relevantfeature being described. The drawings are not necessarily to scale andthe proportions of certain parts may be exaggerated to better illustratedetails and features. The description is not to be considered aslimiting the scope of the embodiments described herein.

The term “comprising” means “including, but not necessarily limited to”;it specifically indicates open-ended inclusion or membership in aso-described combination, group, series, and the like. The disclosure isillustrated by way of example and not by way of limitation in thefigures of the accompanying drawings in which like references indicatesimilar elements. It should be noted that references to “an” or “one”embodiment in this disclosure are not necessarily to the sameembodiment, and such references can mean “at least one.”

The present disclosure provides a voltage output circuit with a simplestructure providing accurate and suitable voltages to different functioncircuits.

First Embodiment

FIG. 1 shows a first embodiment of the voltage output circuit 100. Asshown in FIG. 1, the voltage output circuit 100 includes a control chipU1 and a step-down switch chip U2.

In detail, the control chip U includes a control signal input terminal11 and a modulation signal output terminal 12. The control signal inputterminal 11 of the control chip U1 is electrically connected with afirst switch element, and is grounded through an initial groundedresistor R1. In one embodiment, the first switch element SW1 can be akey, an airflow sensor, and so on. The airflow sensor is used fordetecting a suction signal generated by user. When the first switchelement SW1 is a key, the control signal input terminal 11 of thecontrol chip U1 receives a system power voltage VCC_BAR through thefirst switch element SW1. When the key is pressed, the first switchelement SW1 turns on, the system power voltage VCC_BAR is applied to thecontrol signal input terminal 11 of the control chip U1, and the controlchip U1 outputs a modulation signal to the step-down switch chip U2through the modulation signal output terminal 12.

In detail, the step-down switch chip U2 includes a first access terminal21, a first control terminal 22, and a second access terminal 23. Thefirst access terminal 21 of the step-down switch chip U2 receives thesystem power voltage VCC_BAR, and the first control terminal 22 of thestep-down switch chip U2 is electrically connected with the modulationsignal output terminal 12 of the control chip U1.

In one embodiment, the control chip U1 can be an N76E003-MSOP10*ICPintegrated chip, not being limited thereto. When the control chip U isan N76E003-MSOP10*ICP integrated chip, the control signal input terminal11 is one pin of AIN5/STADC/IC3/PWM3/P0-4 pins of the integrated chip.The modulation signal output terminal 12 is one pin of P0-6/TXD/AIN3pins of the integrated chip.

In one embodiment, the step-down switch chip U2 is a DTQ3205 integratedchip with positive channel metal oxide semiconductors (PMOSs), not beinglimited thereto. The first access terminal 21 of the step-down switchchip U2 is a source electrode. The second access terminal 23 of thestep-down switch chip U2 is a drain electrode. The first controlterminal 22 is a gate electrode. In other embodiments, the step-downswitch chip U2 can be other models or other types of the integratedchip.

In detail, when the first switch element SW1 turns on, the controlsignal input terminal 11 receives a signal in a high voltage level(logic high signal), thus the modulation signal output terminal 12 ofthe control chip U1 outputs the pulse modulation signal to the firstcontrol terminal 22 of the step-down switch chip U2. Access isestablished between the first access terminal 21 and the second accessterminal 23 based on the pulse modulation signal at the first controlterminal 22 of the step-down switch chip U2. When the transistor in thestep-down switch chip U2 is the PMOS, an effective signal of the pulsemodulation signal is a low voltage level (logic low signal). The outputvoltage VOUT of the second access terminal 23 is less than the systempower voltage VCC_BAR.

In one embodiment, the control signal input terminal 11 of the controlchip U1 receives the system power voltage VCC_BAR through a firstcurrent limiting resistor R2 and the first switch element SW1, and/orthe first control terminal 22 of the step-down switch chip U2 iselectrically connected with the modulation signal output terminal 12through a second current limiting resistor R3.

In one embodiment, the control chip U1 can further include a first powerreceiving terminal 13 and a first ground terminal 14. The first powerreceiving terminal 13 receives the system power voltage VCC_BAR througha first filter resistor R4, and is further electrically connected withthe first ground terminal 14 of the control chip U1 through a firstfilter capacitor C1 and a second filter capacitor C2, these beingelectrically interconnected in parallel.

In one embodiment, the first power receiving terminal 13 and the firstground terminal 14 are respectively a VDD pin and a GND pin of theintegrated chip in a N76E003-MSOP10*ICP model, not being limitedthereto.

In one embodiment, the second access terminal 23 of the step-down switchchip U2 is electrically connected with a thermal wire (not shown), foroutputting a driving voltage VOUT, the thermal wire is thus heated bythe driving voltage VOUT for operating an atomizing function.

The voltage output circuit 100 in the embodiment provides the pulsemodulation signal by the control chip U1 to the step-down switch chipU2, and the step-down switch chip U2 can adjust the driving voltage VOUTbased on the pulse modulation signal. Being less than the system powervoltage VCC_BAR, the driving voltage VOUT is provided to a load, such asthe thermal wire. Thus, the driving voltage VOUT outputted by thevoltage output circuit 100 is adjustable, and the structure of thevoltage output circuit 100 is made simple by using the control chip U1and the step-down switch chip U2. In addition, the first limitingresistor R1 and the second limiting resistor R2 serve ascurrent-limiting elements for protecting the voltage output circuit 100against damage, thus a stability of the voltage output circuit 100 isimproved.

Second Embodiment

FIG. 2 shows a second embodiment of the voltage output circuit 200. Asshown in FIG. 2, the voltage output circuit 200 according to the secondembodiment is substantially the same as the voltage output circuit 100according to the first embodiment, and the difference is the controlchip U1. In the second embodiment, the control chip U1 further caninclude an enable signal detection output terminal 15, a first currentreceiving terminal 16, and a second current receiving terminal 17. Thevoltage output circuit 200 of the second embodiment further includes aresistance detection circuit 110. The enable signal detection outputterminal 15 is electrically connected with the resistance detectioncircuit 110.

In one embodiment, the enable signal detection output terminal 15, thefirst current receiving terminal 16, and the second current receivingterminal 17 are respectively one pin of AIN7/CLO/IC1/PWM1/P1 pins, onepin of AIN6/IC5/PWM5/P0-3 pins, and one pin of P0-6/TXD/AIN3 pins of theintegrated chip in an N76E003-MSOP10*ICP model.

The resistance detection circuit 110 can include a third currentlimiting resistor R5, a fourth current limiting resistor R6, a firstdetection resistor R7, a second detection resistor R8, a third detectionresistor R9, a third filter capacitor C3, a fourth filter capacitor C4,and a second switch element SW2. A third access terminal of the secondswitch element SW2 receives the system power voltage VCC_BAR and iselectrically connected with the enable signal detection output terminal15 of the control chip U through the third current limiting resistor R5.A second control terminal of the second switch element SW2 iselectrically connected with the enable signal detection output terminal15 through the fourth current limiting resistor R6. A fourth accessterminal of the second switch element SW2 is electrically connected withthe second access terminal 23 through the first detection resistor R7.One terminal of the second detection resistor R8 is grounded through thethird filter capacitor C3, and the other terminal of the seconddetection resistor R8 is electrically connected with the second accessterminal 23 of the step-down switch chip U2. One terminal of the thirddetection resistor R9 is grounded through the fourth filter capacitorC4, and further is electrically connected with the second currentreceiving terminal 17 of the control chip U1. Another terminal of thethird detection resistor R9 is electrically connected with the fourthaccess terminal of the second switch element SW2.

In one embodiment, the second switch element SW2 is a PNP typetransistor. The third access terminal of the second switch element SW2is an emitter electrode, the second control terminal of the secondswitch element SW2 is a base electrode, and the fourth access terminalof the second switch element SW2 is a collector electrode. In otherembodiments, the second switch element SW2 can be other types oftransistor, such as a PMOS transistor.

The operation of the voltage output circuit 200 of this embodiment withthe PNP transistor as the second switch element SW2 is as follows. Indetail, when the first switch element SW1 turns off, the enable signaldetection output terminal 15 of the control chip U1 outputs a logic lowsignal, the second switch element SW2 turns on. The first currentreceiving terminal 16 and the second current receiving terminal 17 ofthe control chip U1 receive the current passing through the seconddetection resistor R8 and the third detection resistor R9. The controlchip U1 calculates a resistance of the thermal wire based on differencein current between the first current receiving terminal 16 and thesecond current receiving terminal 17.

In one embodiment, the voltage output circuit 200 with the resistancedetection circuit 110 can detect a resistance of the thermal wire basedon a current difference outputted by the resistance detection circuit110. Thus, a duty ratio of the pulse modulation signal can be adjustedbased on the resistance of the thermal wire for adjusting the drivingvoltage VOUT provided to the thermal wire, more flexibility of thevoltage output circuit 200 is provided.

Third Embodiment

FIG. 3 shows a third embodiment of the voltage output circuit 300. Asshown in FIG. 3, the voltage output circuit 300 according to the thirdembodiment is substantially the same as the voltage output circuit 100according to the second embodiment, and the difference is the controlchip U1. In the third embodiment, the control chip U1 further caninclude at least one indicator light control terminal 18. In oneembodiment, there are three indicator light control terminals in thisthird embodiment, as shown in FIG. 3. Each indicator light controlterminal 18 is electrically connected with an indicator circuit 400.

The indicator circuit 400 includes at least one fifth current limitingresistor R10 and at least one first light emitting diode (LED) D1. Acathode of each LED D1 is electrically connected with one indicatorlight control terminal 18 through a fifth current limiting resistor R10,and an anode of each LED D1 receives the system power voltage VCC_BAR.

The voltage output circuit 300 in the third embodiment electricallyconnects with the indicator circuit 400 and controls the LED D1 to belit through the indicator light control terminal 18 for indicating powerof a chargeable battery.

An electronic cigarette with the voltage output circuit 100, or 200, or300 is also provided.

In this embodiment, the electronic cigarette can further include acharging circuit 500. FIG. 4 shows a circuit diagram of the chargingcircuit 500. As shown in FIG. 4, the charging circuit 500 can include aconnector J1 and a charging chip U3.

In detail, the charging chip U3 can include a second power receivingterminal 31 and a charging voltage output terminal 32. The second powerreceiving terminal 31 is electrically connected with an external powersource through the connector J1. The charging voltage output terminal 32outputs a charging voltage to a positive terminal BAT+ of the chargeablebattery.

In one embodiment, the charging chip U3 is a BQ24040 integrated chip,not being limited thereto. The second power receiving terminal 31 andthe charging voltage output terminal are the IN pin and OUT pin of theBQ24040 integrated chip.

In one embodiment, the charging circuit 500 can further include acharging protection chip U4. The charging protection chip U4 includes athird power receiving terminal 41, a second ground terminal 42, a heatdissipation lump terminal 43, and a charging detection terminal 44.

In detail, the third power receiving terminal 41 of the chargingprotection chip U4 is electrically connected with the positive electrodeBAT+ of the chargeable battery. The second ground terminal 42 of thecharging protection chip U4 is electrically connected with a negativeelectrode BAT− of the chargeable battery. The heat dissipation lumpterminal 43 of the charging protection chip U4 is electrically connectedwith the second ground terminal 42 of the charging protection chip U4.The charging detection terminal 44 of the charging protection chip U4 isgrounded. The heat dissipation lump terminal 43 of the chargingprotection chip U4 is used for decreasing a temperature of the chargingprotection chip U4 from being damaged by a high temperature. The heatdissipation lump terminal 43 of the charging protection chip U4 isconnected with the second ground terminal 42 of the charging protectionchip U4. A size of grounding area of the charging protection chip U4 islarger, thus a current flow capability of the voltage output circuit 100is improved.

In detail, the charging protection chip U4 protects the chargeablebattery from being overcharged, or being short-circuited, or beingover-discharged. The second ground terminal 42 of the chargingprotection chip U4 is electrically connected with the negative electrodeBAT− of the chargeable battery, and the charging detection terminal 44of the charging protection chip U4 is grounded, thus the negativeelectrode BAT− of the chargeable battery is not connected directly toground, and the charging protection chip U4 is located between thenegative electrode BAT− of the chargeable battery and a system ground.When the chargeable battery needs to be charged or discharged, thenegative electrode BAT− of the chargeable battery is electricallyconnected to the ground through the charging protection chip U4. Thus,the charging protection chip U4 in the voltage output circuit 100detects the voltage or the current on its own pins or its own elementsto determine whether the chargeable battery is in a state of beingover-discharged or is being overcharged. When in such states, theconnection between the negative electrode BAT− of the chargeable batteryand the ground is disconnected for protecting the chargeable battery.

In one embodiment, the second ground terminal 42 of the chargingprotection chip U4 is electrically connected with one terminal of thefifth filter capacitor C5, and another terminal of the fifth filtercapacitor C5 is electrically connected with the negative electrode BAT−of the chargeable battery. The fifth filter capacitor C5 filters thesystem power voltage VCC_BAR from the positive electrode BAT+ of thechargeable battery.

In one embodiment, the charging protection chip U4 is XB6006A2. As shownin FIG. 4, the third power receiving terminal 41 of the chargingprotection chip U4 is a VDD terminal, the second ground terminal 42 is aGND terminal, the heat dissipation lump terminal 43 is an EPAD terminal,and the charging detection terminal 44 is a VM terminal.

The electronic cigarette of the embodiment can automatically disconnectthe connection between the chargeable battery and the charging chip U3or between the chargeable battery and a discharging path by the chargingprotection chip U4. Overcharging and/or over-discharging of thechargeable battery and the electronic cigarette are thus prevented, boththe electronic cigarette and the chargeable battery are protected.

The voltage output circuit 100 and the electronic cigarette outputs thepulse modulation signal to the step-down switch chip U2 for controllingthe driving voltage VOUT. The driving voltage VOUT provided to the load,such as to the thermal wire as a load, can be lower than the systempower voltage VCC_BAR. Thus, the voltage outputted by the voltage outputcircuit 100 can be adjusted, and the structure of the voltage outputcircuit 100 is simplified by using the control chip U and the step-downswitch chip U2.

Fourth Embodiment

FIG. 5 shows a fourth embodiment of the voltage output circuit 600. Thecontrol chip U1 in FIG. 5 includes a control signal input terminal 11and a modulation signal output terminal 12. The control signal inputterminal 11 of the control chip U1 is electrically connected with afirst switch element SW1, and is grounded through an initial groundedresistor R1. In detail, the control chip U further includes a firstpower receiving terminal 13 and a first grounding terminal 14. The firstpower receiving terminal 13 is electrically connected with a positiveelectrode BAT+ of the battery, and receives the system power voltage.The first power receiving terminal 13 is grounded through a sixth filtercapacitor C6, and receives a stable voltage. Besides, the firstgrounding terminal 14 is grounded.

In detail, the step-down switch chip U2 includes a first access terminal21, a first control terminal 22, and a second access terminal 23. Thefirst access terminal 21 of the step-down switch chip U2 receives thesystem power voltage VCC_BAR, and the first control terminal 22 of thestep-down switch chip U2 is electrically connected with the modulationsignal output terminal 12 of the control chip U1. Optionally, the firstcontrol terminal 22 of the step-down switch chip U2 receives the systempower voltage through a seventh current limiting resistor R16. Thesecond access terminal 23 of the step-down switch chip U2 iselectrically connected with a thermal wire S for outputting a drivingvoltage to the thermal wire S, and the thermal wire S operates togenerate heat.

In one embodiment, the step-down switch chip U2 can be a DTQ3205integrated chip with positive channel metal oxide semiconductors(PMOSs), not being limited thereto. The first access terminal 21 of thestep-down switch chip U2 is a source electrode. The second accessterminal 23 of the step-down switch chip U2 is a drain electrode. Thefirst control terminal 22 is a gate electrode. In other embodiments, thestep-down switch chip U2 can be other models or other types of theintegrated chip.

In one embodiment, the first switch element SW1 is an airflow sensor,such as a microphone. The first switch element SW1 detects a suctionsignal generated by a user for determining whether the user is drawingon the electronic cigarette. When the suction signal is detected by theairflow sensor, the airflow sensor generates an enable signal to thecontrol chip U1.

As shown in FIG. 5, a power terminal 71 of the airflow sensor U7 iselectrically connected with a positive electrode BAT+ of the chargeablebattery, and is used for receiving the system power voltage VCC_BAR. Thecontrol signal input terminal 11 of the control chip U is electricallyconnected with a signal output terminal 72 of the airflow sensor U7through a sixth current limiting resistor R11, and the signal outputterminal 72 of the airflow sensor U7 is grounded through the initialground resistor R1. A grounding terminal 73 of the airflow sensor U7 isgrounded. The initial grounding resistor R1 is used as a pull-downresistor. When the suction action is detected by the airflow sensor U7,the airflow sensor U7 outputs the enable signal to the control signalinput terminal 11 of the control chip U1 through the signal outputterminal 72. When the control chip U1 receives the enable signal, thecontrol chip U1 outputs the pulse modulation signal to the step-downswitch chip U2 through the modulation signal output terminal 12.

In detail, the first control terminal 22 of the step-down switch chip U2is electrically connected with the modulation signal output terminal 12of the control chip U1 through a second current limiting resistor R3.The first control terminal 22 of the step-down switch chip U2 receivesthe system power voltage VCC_BAR through a seventh current limitingresistor R16.

In detail, the second access terminal 23 of the step-down switch chip U2is electrically connected with a resistance detection terminal 19 of thecontrol chip U1 through a fourth detection resistor R13. The resistancedetection terminal 19 is electrically connected with a terminal of adivider resistor R14 through the fourth detection resistor R13. Anotherterminal of the divider resistor R14 is grounded. The second accessterminal 23 of the step-down switch chip U2 is grounded through thedivider resistor R14. In one embodiment, the fourth detection resistorR13 and the divider resistor R14 can detects a resistance of the thermalwire, for determining whether the thermal wire S is correctly installed.Optionally, the fourth detection resistor R13 and the divider resistorR14 in the voltage output circuit 600 can be omitted, and the secondaccess terminal 23 of the step-down switch unit U2 is directly connectedwith the resistance detection circuit 110 of the second embodiment, acurrent difference outputted by the resistance detection circuit 110 isused for acquiring a resistance of the thermal wire S. and the dutyratio of the pulse modulation signal is adjusted by the resistance ofthe thermal wire S, the driving voltage VOUT provided to the thermalwire S is adjusted, and more flexibility of the voltage output circuit600 is improved.

Optionally, the voltage output circuit 600 in the embodiment furtherincludes a voltage stabilizing module U5. A first terminal 51 of thevoltage stabilizing module U5 is electrically connected with a voltageoutput terminal 111 of the control chip U1 through a stabilizingresistor R15. The first terminal 51 of the stabilizing module U5 iselectrically connected with a second terminal 52 of the stabilizingmodule U5. The second terminal 52 of the stabilizing module U5 iselectrically connected with a high voltage level input terminal 112 ofthe control chip U1. The stabilizing module U5 is set in the voltageoutput circuit 600 in the embodiment to stabilize an internal voltage ofthe control chip U1 at a predetermined voltage, for preventing thecontrol chip U1 being damaged while operated under an unstable voltage.

Optionally, the control chip U1 further includes at least one indicatorlight control terminal 18. Each indicator light control terminal 18 iselectrically connected with an indicator circuit 700.

The indicator circuit 700 includes at least one fifth current limitingresistor R10 and at least one light emitting diode (LED) D1. A cathodeof each LED D1 can be electrically connected with one indicator lightcontrol terminal 18 through a fifth current limiting resistor R10.Cathodes of the LED D1 also can be electrically connected with a singleindicator light control terminal 18 through a single fifth currentlimiting resistor R10.

As shown in FIG. 5, there are two indicator light control terminals 18.Each indicator light control terminal 18 is electrically connected witha terminal of the LED D1 through the fifth current limiting resistorR10. Another terminal of the LED D1 is electrically connected with thecontrol signal input terminal 11 of the control chip U1. Optionally, asshown in FIG. 5, the terminals of the two LEDs D1 are electricallyconnected with the indicator light control terminal 18 of the controlchip U1 through a single fifth current limiting resistor R10, otherterminals of the two LEDs D1 are electrically connected with the controlsignal input terminal 11 of the control chip U1. A terminal of a thirdLED D is electrically connected with the adjacent indicator lightcontrol terminal 18 of the control chip U1 through a second fifthcurrent limiting resistor R10, other terminal of the third LED D1 iselectrically connected with the control signal input terminal 11 of thecontrol chip U1. The three LEDs D1 can be illuminated or be dark underthe control of the control signal input terminal 11 and the indicatorlight control terminal 18.

The voltage output circuit 600 in the embodiment is electricallyconnected with the indicator circuit 700, and the LEDs D1 are controlledto be illuminated through the indicator light control terminal 18, forindicating the energy of the chargeable battery, for example, a highenergy is green light, and a low energy is red light. Besides, theindicator circuit 700 also indicates a current power or an outputvoltage, for example, a high power is red light, and a low power isgreen light. The indicator circuit 700 also indicates a drawing(suction) or non-drawing (no suction) state of the user. When the usersmokes the electronic cigarette, the LED D1 is illuminated. When theuser stops smoking, the LED D1 is dark. In one embodiment, there areLEDs D1 with different colors. A color of the indicator when illuminatedof the electronic cigarette is adjusted by controlling one or more ofthe LEDs D1 with different illumination colors. For example, a displayedcolor of the indicator when illuminated of the electronic cigarette canbe yellow by controlling the illumination, or respective illumination,of the red LED D1 and the green LED D1. The adjusting manner is notlimited.

In one embodiment, the second access terminal 23 of the step-down switchchip U2 is electrically connected with the thermal wire S and outputsthe driving voltage for driving the thermal wire S to generate heat.

The present disclosure also provide a second embodiment of theelectronic cigarette with the voltage output circuit 600.

In one embodiment, the electronic cigarette further includes a chargingcircuit 800. FIG. 6 shows an embodiment of the charging circuit 800. Thecharging circuit 800 includes a connector J1 and a charging chip U3.

In detail, the charging chip U3 includes a second power receivingterminal 31 and a charging voltage output terminal 32. The second powerreceiving terminal 31 is electrically connected with an external powersource through the connector J1. The charging voltage output terminal 32outputs a charging voltage to a positive terminal BAT+ of the chargeablebattery. In one embodiment, the charging chip U3 is an MP2602 integratedchip, not being limited thereto. The second power receiving terminal 31and the charging voltage output terminal are the VIN pin and BATT pin ofthe MP2602 integrated chip.

Optionally, in another embodiment, the charging circuit 800 furtherincludes a battery protection chip U6. The battery protection chip U6 isused for protecting the chargeable battery from being overcharged orbeing over-discharged. The battery protection chip U6 includes acharging input terminal 61, a third ground terminal 62, a fourth groundterminal 63, a fourth power receiving terminal 64, and an internal powersupply terminal 65. In one embodiment, the charging input terminal 61 iselectrically connected with charging voltage output terminal 32 of thecharging chip U3, and is grounded through a seventh filter capacitor C7for receiving a stable voltage. The third ground terminal 62 and thefourth ground terminal 63 are grounded. The internal power supplyterminal 65 is grounded through an eighth capacitor C8. The fourth powerreceiving terminal 64 is electrically connected with a positiveelectrode BAT+ of the chargeable battery. A negative electrode BAT− ofthe chargeable battery is grounded. Optionally, the battery protectionchip U6 is a CT2105 chip, not being limited thereto. When the batteryprotection chip U6 is the CT2105 chip, the charging input terminal 61 ofthe battery protection chip U6 is a VM pin, and the third groundterminal 62 and the fourth ground terminal 63 are GND pins. The fourthpower receiving terminal 64 is a VDD pin, and the internal power supplyterminal 65 is a VCC pin. In one embodiment, when the battery protectionchip U6 detects that the chargeable battery is being overcharged or isbeing over-discharged, the battery protection chip U6 disconnects aconnection between the fourth power receiving terminal 64 and thechargeable battery, for disconnecting the chargeable battery from thevoltage output circuit 600 and/or the charging circuit 800.

Besides, in one embodiment, the electronic cigarette can include achargeable battery. In other embodiments, the chargeable battery can beomitted, not being limited thereto. The types of the chargeable batterycan be a chargeable or a non-chargeable battery, such as, a lithiumbattery, an alkaline dry battery, a nickel metal hydride battery, alead-acid battery, an iron nickel battery, a metal oxide battery, azinc-silver battery, a zinc-nickel battery, a hydrogen-oxygen fuelbattery, and a solar battery.

While various and preferred embodiments have been described thedisclosure is not limited thereto. On the contrary, variousmodifications and similar arrangements (as would be apparent to thoseskilled in the art) are also intended to be covered. Therefore, thescope of the appended claims should be accorded the broadestinterpretation so as to encompass all such modifications and similararrangements.

What is claimed is:
 1. A voltage output circuit comprising: a controlchip with a control signal input terminal and a modulation signal outputterminal, the control signal input terminal receives a system powervoltage through a first switch element, and is grounded through aninitial ground resistor; the first switch element generates an enablesignal to the control chip when being energized; and a step-down switchchip with a first access terminal, a first control terminal, and asecond access terminal; the first access terminal receives the systempower voltage, the first control terminal is electrically connected withthe modulation signal output terminal of the control chip; wherein whenthe first switch element is energized, the control chip receives theenable signal, and the modulation signal output terminal of the controlchip outputs a pulse modulation signal to the first control terminal ofthe step-down switch chip, and an access is formed between the firstaccess terminal and the second access terminal based on the effectivepulse modulation signal at the first control terminal of the step-downswitch chip; the output voltage of the second access terminal is lessthan the system power voltage.
 2. The voltage output circuit of claim 1,wherein the control signal input terminal receives the system powervoltage through a first current limiting resistor and the first switchelement; the first control terminal is electrically connected with themodulation signal output terminal through a second current limitingresistor.
 3. The voltage output circuit of claim 1, wherein the controlchip further comprises a first power receiving terminal and a firstground terminal; the first power receiving terminal receives the systempower voltage through a first filter resistor, and is furtherelectrically connected with the first ground terminal through the firstfilter capacitor and a second filter capacitor, which are electricallyconnected with each other in parallel.
 4. The voltage output circuit ofclaim 1, wherein the second access terminal of the step-down switch chipis electrically connected with a thermal wire for outputting a drivingvoltage, which drives the thermal wire to generate heat.
 5. The voltageoutput circuit of claim 4, wherein the control chip further comprises anenable signal detection output terminal, a first current receivingterminal, and a second current receiving terminal; the voltage outputcircuit further comprises a resistance detection circuit; the enablesignal detection output terminal is electrically connected with theresistance detection circuit; the resistance detection circuit comprisesthird current limiting resistor, a fourth current limiting resistor, afirst detection resistor, a second detection resistor, a third detectionresistor, a third filter capacitor, a fourth filter capacitor, and asecond switch element; the third access terminal of the second switchelement receives the system power voltage, and is electrically connectedwith the enable signal detection output terminal through the thirdcurrent limiting resistor, a second control terminal of the secondswitch element is electrically connected with the enable signaldetection output terminal through the fourth current limiting resistor;a fourth access terminal of the second switch element is electricallyconnected with the second access terminal through the first detectionresistor, one terminal of the second detection resistor is groundedthrough the third filter capacitor, and other terminal of the seconddetection resistor is electrically connected with the second accessterminal; one terminal of the third detection resistor is groundedthrough the fourth filter capacitor, and further is electricallyconnected with the second current receiving terminal; other terminal ofthe third detection resistor is electrically connected with the fourthaccess terminal of the second switch element.
 6. The voltage outputcircuit of claim 1, wherein the control chip further comprises an enablesignal detection output terminal, a first current receiving terminal,and a second current receiving terminal; the voltage output circuitfurther comprises a resistance detection circuit; the enable signaldetection output terminal is electrically connected with the resistancedetection circuit; the resistance detection circuit comprises thirdcurrent limiting resistor, a fourth current limiting resistor, a firstdetection resistor, a second detection resistor, a third detectionresistor, a third filter capacitor, a fourth filter capacitor, and asecond switch element; the third access terminal of the second switchelement receives the system power voltage, and is electrically connectedwith the enable signal detection output terminal through the thirdcurrent limiting resistor, a second control terminal of the secondswitch element is electrically connected with the enable signaldetection output terminal through the fourth current limiting resistor;a fourth access terminal of the second switch element is electricallyconnected with the second access terminal through the first detectionresistor, one terminal of the second detection resistor is groundedthrough the third filter capacitor, and another terminal of the seconddetection resistor is electrically connected with the second accessterminal; one terminal of the third detection resistor is groundedthrough the fourth filter capacitor, and further is electricallyconnected with the second current receiving terminal; another terminalof the third detection resistor is electrically connected with thefourth access terminal of the second switch element.
 7. The voltageoutput circuit of claim 1, wherein the control chip further comprises atleast one indicator light control terminal; each indicator light controlterminal is electrically connected with an indicator circuit; theindicator circuit comprises at least one fifth current limiting resistorand at least one LED; a cathode of each LED is electrically connectedwith one indicator light control terminal through a fifth currentlimiting resistor, and an anode of each LED receives the system powervoltage.
 8. The voltage output circuit of claim 1, wherein the firstswitch element is an airflow sensor; a power terminal of the airflowsensor receives the system voltage; the control signal input terminal ofthe control chip is electrically connected with a signal output terminalof the airflow sensor through a sixth current limiting resistor, thesignal output terminal is grounded through the initial ground resistor.9. The voltage output circuit of claim 8, wherein the control chipfurther comprises a first power receiving terminal and a first groundterminal; the first power receiving terminal of the control chipreceives the system power voltage, and is grounded through a sixthfilter capacitor; the first ground terminal is grounded.
 10. The voltageoutput circuit of claim 9, wherein the first control terminal of thestep-down switch chip receives the system power voltage through aseventh current limit resistor, the second access terminal of thestep-down switch chip is connected with a resistance detection terminalof the control chip through a fourth detection resistor, the resistancedetection terminal is connected with a terminal of a divider resistorthrough the fourth detection resistor, other terminal of the dividerresistor is grounded; the second access terminal of the step-down switchchip is grounded through the divider resistor.
 11. The voltage outputcircuit of claim 8, wherein the voltage output circuit further comprisesa voltage stabilizing module; a first terminal of the voltagestabilizing module is connected with a voltage output terminal of thecontrol chip through a stabilizing resistor; the first terminal of thestabilizing module is connected with a second terminal of thestabilizing module; the second terminal of the stabilizing module isconnected with a high voltage level input terminal of the control chip.12. An electronic cigarette comprising: a voltage output circuit; thevoltage output circuit comprising: a control chip with a control signalinput terminal and a modulation signal output terminal, the controlsignal input terminal receives a system power voltage through a firstswitch element, and is grounded through an initial ground resistor; thefirst switch element generates an enable signal to the control chip whenbeing energized; and a step-down switch chip with a first accessterminal, a first control terminal, and a second access terminal; thefirst access terminal receives the system power voltage, the firstcontrol terminal is connected with the modulation signal output terminalof the control chip; wherein when the first switch element is energized,the control chip receives the enable signal, and the modulation signaloutput terminal of the control chip outputs a pulse modulation signal tothe first control terminal of the step-down switch chip, and an accessis formed between the first access terminal and the second accessterminal based on the effective pulse modulation signal at the firstcontrol terminal of the step-down switch chip; the output voltage of thesecond access terminal is less than the system power voltage.
 13. Theelectronic cigarette of claim 12, wherein the control signal inputterminal receives the system power voltage through a first currentlimiting resistor and the first switch element; the first controlterminal is electrically connected with the modulation signal outputterminal through a second current limiting resistor.
 14. The electroniccigarette of claim 12, wherein the control chip further comprises afirst power receiving terminal and a first ground terminal; the firstpower receiving terminal receives the system power voltage through afirst filter resistor, and is further electrically connected with thefirst ground terminal through a first filter capacitor and a secondfilter capacitor, which are electrically connected with each other inparallel.
 15. The electronic cigarette of claim 12, wherein the secondaccess terminal of the step-down switch chip is electrically connectedwith a thermal wire for outputting a driving voltage, which drives thethermal wire to generate heat.
 16. The electronic cigarette of claim 12,wherein the control chip further comprises at least one indicator lightcontrol terminal; each indicator light control terminal is electricallyconnected with an indicator circuit; the indicator circuit comprises atleast one fifth current limiting resistor and at least one LED; acathode of each LED is electrically connected with one indicator lightcontrol terminal through a fifth current limiting resistor, and an anodeof each LED receives the system power voltage.
 17. The electroniccigarette of claim 12, wherein the electronic cigarette furthercomprises a chargeable battery; the chargeable battery provides thesystem power voltage.
 18. The electronic cigarette of claim 17, whereinthe electronic cigarette further comprises a connector and a chargingchip; the charging chip comprises a second power receiving terminal anda charging voltage output terminal; the second power receiving terminalis electrically connected with an external power source through theconnector; the charging voltage output terminal outputs a chargingvoltage to a positive terminal of the chargeable battery.
 19. Theelectronic cigarette of claim 18, wherein the electronic cigarettefurther comprises a charging protection chip; the charging protectionchip comprises a third power receiving terminal, a second groundterminal, a heat dissipation lump terminal, and a charging detectionterminal; the third power receiving terminal of the charging protectionchip is electrically connected with the positive electrode of thechargeable battery; the second ground terminal of the chargingprotection chip is electrically connected with a negative electrode ofthe chargeable battery; the heat dissipation lump terminal of thecharging protection chip is electrically connected with the secondground terminal of the charging protection chip; the charging detectionterminal of the charging protection chip is grounded.
 20. The electroniccigarette of claim 19, wherein the charging circuit further comprises abattery protection chip; the battery protection chip comprises acharging input terminal, a third ground terminal, a fourth groundterminal, a fourth power receiving terminal, and an internal powersupply terminal; the charging input terminal is connected with chargingvoltage output terminal of the charging chip, and is grounded through aseventh filter capacitor for receiving a stable voltage; the thirdground terminal and the fourth ground terminal are grounded; theinternal power supply terminal is grounded through an eighth capacitor;the fourth power receiving terminal is connected with a positiveelectrode of the chargeable batter; a negative electrode of thechargeable battery is grounded.